He joined the Department of French Literature in the University of California, Berkeley as an assistant professor in 1976 at the age of 27, and from 1989 to 2014 he was professor of History of Ideas in the École Polytechnique department of humanities and social sciences.

In 2010, he was involved in founding JCall, a left-wing zionist advocacy group based in Europe to lobby the European Parliament on foreign policy issues concerning the Middle East. He is a strong supporter of Israel and the two-state solution.

Finkielkraut first came to public attention when he and Pascal Bruckner co-authored a number of short but controversial essays intended to question the idea that a new emancipation was underway; these included The New Love Disorder (1977) (Le Nouveau Désordre amoureux) and At The Corner Of The Street (1978) (Au Coin de la rue), as well as The Adventure (1979) (L'aventure). Finkielkraut then began publishing singly authored works on the public's betrayal of memory and our intransigence in the presence of events which, he argued, should move the public. This reflection led Finkielkraut to address post-Holocaust Jewish identity in Europe (The Imaginary Jew) (1983) (le Juif imaginaire). Seeking to promote what he calls a duty of memory, Finkielkraut also published The Future Of A Negation: Reflexion On The Genocide Issue (1982) (Avenir d'une négation : réflexion sur la question du génocide) and later his comments on the Klaus Barbie trial, Remembering in Vain (La Mémoire vaine).

Finkielkraut feels particularly indebted to Emmanuel Levinas. In The Wisdom of Love (La Sagesse de l'amour), Finkielkraut discusses this debt in terms of modernity and its mirages. Finkielkraut continues his reflection on the matter in The Defeat of the Mind (1987) (La Défaite de la pensée), The Ingratitude: Talks about our Times (1999) (Ingratitude : conversation sur notre temps).

In recent years, Alain Finkielkraut has given his opinion on a variety of topics regarding society, for instance the Internet in The Internet, The Troubling Ecstasy (2001) (Internet, l'inquiétante extase). In the book Present Imperfect (2002) (L'Imparfait du présent), akin to a personal diary, he expresses his thoughts about various events in the world (especially the events of 11 September 2001).

During the wars resulting from the Breakup of Yugoslavia, he was one of the first to strongly condemn Serbian ethnic cleansing. However, he has been criticised for his close friendship with Croatian president Franjo Tuđman and was accused by David Bruce MacDonald of supporting "a nation whose leader was a Holocaust denier, at the helm of an authoritarian government."[2]

His interview published in the Haaretz magazine in November 2005 in which he gave his opinion about the 2005 French riots stirred up much controversy. Finkielkraut's remarks that the French Soccer Team was "Black, Black, Black" (as opposed to the expression "Black, Blanc, Beur"—meaning "Black, White, Arab"—coined after the 1998 World Cup victory to honor the African and Afro Caribbean, European and North African origins of the players) were seen as "racially insensitive".

Israeli filmmaker Eyal Sivan took legal action against Finkielkraut after the Frenchman said Sivan "is, if you will, one of the actors in this particularly painful, particularly alarming reality, the Jewish anti-Semitism that rages today."[3]

In 2009, he was criticized for his strong defence of Roman Polanski, arrested in Switzerland for illegal sexual relationships with a 13-year-old girl. Finkielkraut claimed that she was a "teenager", "not a child".[5]